1. Field of the Invention
This invention is directed to higher diamondoid derivatives containing moieties that are capable of undergoing polymerization. This invention is further directed to processes for polymerizing such derivatives, to chemical intermediates useful for the synthesis of such derivatives and to polymers based upon these derivatives.
2. References
The following publications and patents are cited in this application as superscript numbers:
1 Fort, Jr., et al., Adamantane: Consequences of the Diamondoid Structure, Chem. Rev., 64:277-300 (1964).
2 Capaldi, et al., Alkenyl Adamantanes, U.S. Pat. No. 3,457,318, issued Jul. 22, 1969.
3 Thompson, Polyamide Polymer of Diamino Methyl Adamantane and Dicarboxylic Acid, U.S. Pat. No. 3,832,332, issued Aug. 27, 1974.
4 Baum, et al., Ethynyl Adamantane Derivatives and Methods of Polymerization Thereof, U.S. Pat. No. 5,017,734, issued May 21, 1991.
5 Ishii, et al., Polymerizable Adamantane Derivatives and Process for Producing Same, U.S. Pat. No. 6,235,851, issued May 22, 2001
6 McKervey, et al., Synthetic Approaches to Large Diamondoid Hydrocarbons, Tetrahedron, 36:971-992 (1980).
7 Lin, et al., Natural Occurrence of Tetramantane (C22H28), Pentamantane (C26H32) and Hexamantane (C30H36) in a Deep Petroleum Reservoir, Fuel, 74(10):1512-1521 (1995).
8 Chen, et al., Isolation of High Purity Diamondoid Fractions and Components, U.S. Pat. No. 5,414,189, issued May 9, 1995.
9 Balaban et al., Systematic Classification and Nomenclature of Diamond Hydrocarbons—I, Tetrahedron. 34, 3599-3606 (1978).
All of the above publications and patents are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent was specifically and individually indicated to be incorporated by reference in its entirety.
3. State of the Art
Diamondoids are cage-shaped hydrocarbon molecules possessing rigid structures resembling tiny fragments of a diamond crystal lattice as described by Fort, Jr., et al.1 Adamantane is the smallest member of the diamondoid series and consists of a single cage structure of the diamond crystal lattice. Diamantane contains two adamantane subunits face-fused to each other, triamantane three, tetramantane four, and so on. While there is only one isomeric form of adamantane, diamantane and triamantane, there are four different isomeric tetramantanes (i.e., four different shapes containing four adamantane subunits). Two of the isomeric tetramantanes are enantiomeric. The number of possible isomers increases rapidly with each higher member of the diamondoid series.
Among other properties, diamondoids have by far the most thermodynamically stable structures of all possible hydrocarbons that possess their molecular formulas due to the fact that diamondoids have the same internal “crystalline lattice” structure as diamonds. It is well established that diamonds exhibit extremely high tensile strength, extremely low chemical reactivity, electrical resistivity greater than aluminum trioxide (Al2O3), excellent thermal conductivity, and superb optical properties.
Adamantane, which is commercially available, has been studied extensively. The studies have been directed to a number of areas, such as thermodynamic stability, functionalization and properties of adamantane-containing materials. For instance, the following patents describe adamantane derivatives and adamantane-based polymers. U.S. Pat. No. 3,457,318 teaches the preparation of polymers from alkenyl adamantanes;2 U.S. Pat. No. 3,832,332 describes a polyamide polymer formed from alkyladamantane diamine;3 U.S. Pat. No. 5,017,734 discusses the formation of thermally stable resins from ethynyl adamantane derivatives;4 and, U.S. Pat. No. 6,235,851 reports the synthesis and polymerization of a variety of adamantane derivatives.5 
The higher diamondoids, which include the tetramantanes, pentamantanes, etc., have received comparatively little attention. In fact, prior to the work of inventors Dahl and Carlson embodied in U.S. Patent Application Ser. No. 60/262,842 filed Jan. 19, 2001 and numerous subsequent filings, these compounds were nearly hypothetical with only one such compound having been synthesized and a few others tentatively identified (but not isolated). More specifically, McKervey, et al. reported the synthesis of anti-tetramantane in low yields using a laborious, multistep process.6 Lin, et al. have suggested the existence of tetramantane, pentamantane and hexamantane in deep petroleum reservoirs from mass spectroscopy alone and without any attempt to isolate materials.7 The possible presence of tetramantane and pentamantane in pot material recovered after a distillation of a diamondoid-containing feedstock has been discussed by Chen, et al.8